1. Field of the Invention
The present invention relates to portable vehicle-stabilized masts and readily deployable and configurable fall protection systems, adaptable for use in cargo-handling environments.
2. Description of the Related Art
The loading and unloading of cargo and materials from vehicles, e.g., a flat bed truck, often requires personnel to be performing strenuous activity at a level several feet above ground level. Loading and unloading requires careful balance and stepping on or around uneven standing areas while carrying or manipulating cargo and while securing and covering the cargo. Moreover, such loading and unloading often occurs outdoors and may occur in adverse weather creating windy and/or slick conditions. Also, cargo may be unwieldy, may shift, and/or have an unstable center of gravity. Thus, for workers performing the loading and unloading tasks, there is an inherent safety risk of falling from a working-level height to the ground.
The Bureau of Labor Statistics has reported that fatal work injuries involving falls number several hundred each year. The Department of Labor lists falls as one of the leading causes of traumatic occupational death, accounting for eight percent of all occupational fatalities from trauma. The Department's general guidance for worker safety provides that any time a worker is at a height of four feet or more, the worker is at risk and needs to be protected. In maritime activities, the distance is five feet and in construction, the distance is six feet. However, regardless of the fall distance, fall protection must be provided when working over dangerous equipment and machinery. In the United States, the Occupational Safety & Health Administration and the labor and safety agencies of many states regulate worksite safety and require that adequate measures be taken to protect workers from falls. Thus, there is a critical need to provide fall protection for workers who are working above ground level, such as on the bed of a flat bed truck.
Previous attempts to provide fall protection safety systems involve many trade-offs. For example, a fall prevention system available from Carbis, Inc. provides two fall prevention platforms between which a flatbed truck is driven and parked. At the press of a button, the platforms move together to sandwich the trailer in the middle. The system also may provide a platform on only one side. Such a system, however, has multiple disadvantages. First, the system is designed for permanent installation at a site rather than mobility for temporary use at various sites such as construction sites. Second, the height of the platform is fixed and cannot be raised or lowered for differing truck and load configurations. Third, ground-level workers and equipment (e.g., loading and unloading equipment) cannot access the platform side(s) of the truck bed. In a similar system from Safe Rack LLC, the platforms are mounted on wheels rather than being part of a permanent installation; however, platform height is not adjustable and ground-level access is equally impaired.
Another fall protection system, Airtek Ireland's AirMat Safety System, may be temporarily deployed at various work sites. The system provides multiple inflatable modules in various sizes to accommodate a variety of truck and trailer length combinations. The modules are inflated by a pump-driven fan to approximately the height of the truck bed and placed alongside the truck or the truck is parked adjacent to inflated modules. If a worker falls from the truck bed to an area protected by one of the modules, the worker's fall is arrested and cushioned by the module. As with the Carbis system, ground-level workers and equipment cannot easily access the side(s) of the truck bed adjacent to the inflated modules. Moreover, a power source must continually be available to operate the fan.
Systems provided by CAI Safety Systems allow a truck to park adjacent to a pair of permanently mounted “T Anchors” or mast arms. A cable or rigid rail is suspended from the T Anchors or mast arms at a height sufficiently above the truck and its cargo. A worker wearing a safety harness is tethered to the cable or rigid rail via a self-retracting lifeline. In case the worker falls, the fall is arrested by the system. Another worker must operate the self-retracting gear from its attachment point at the cable or rigid rail in order to lower the fallen worker to the ground. In an alternate arrangement interior to a building, the cable or rigid rail may be suspended from the building's overhead structure. Being permanently mounted to the ground or attached to a building structure, these systems cannot be easily deployed to temporary work sites.
Japanese Patent Application JP2000-210389 discloses a dollied strut, two of which are wheeled up to a truck and affixed to the truck at several points. Once the struts are affixed to the truck, a rope is stretched between the tops of the struts and a lifeline is used to connect the rope and an on-vehicle worker. A disadvantage of this system is that the struts must be mechanically connected to the vehicle structure upon arrival of the vehicle at the work site in order for a worker to be able to safely work on the vehicle; conversely, the vehicle cannot depart upon completion of on-vehicle work until the system is mechanically disconnected from the vehicle structure. Moreover, trucks must be modified to have reciprocal attachment points for the struts. Also, due to the positioning of strut support members on and above the truck bed, free ground-level access to the truck bed and cargo is impeded.
Thus, the systems mentioned above suffer from a number of deficiencies and disadvantages. The present invention can provide for easily deployable fall safety systems, easily configurable for use with differently-sized vehicles. Moreover the present invention does not require vehicles to be modified with attachment points and cargo areas remain accessible to ground-level personnel and equipment.